West Mata
| West Mata | ||
|---|---|---|
 West Mata eruption in May 2009 |
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| height | 1000 m below sea level | |
| location | Pacific | |
| Coordinates | 15 ° 6 ′ 4 " S , 173 ° 45 ′ 32" W | |
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West Mata is a submarine volcano located about 200 km southwest of Samoa in the Pacific .
The summit crater is 1000 m below the sea surface. The volcano is currently one of the lowest known submarine volcanoes and the first to have an eruption filmed.
Geological classification
Accurate location
West Mata is just to the west of the northern end of the Tonga Ridge, where the Tonga Trench makes a sharp bend to the west. It is located in the northeast of the Lau Depression about 35 km east of the Lau expansion zone and 70 km northeast of its constantly erupting volcano.
First news of an outbreak
As early as November 2008, it was announced that an undersea eruption was likely to have occurred at the site.
exploration
The research vessel Thompson explored the area between November 2008 and May 2009. In November 2008, the researchers saw an eruption column over West Mata that indicated an active lava flow or pyroclastic flow .
Upon closer inspection, it turned out that the eruption column contained glass fragments that were rich in sulfur and iron . Laboratory tests have shown that the ejecta is composed of boninite , an olivine - bronzite - andesite without feldspar , a mixture that had never been found in an active volcano, but only in an extinct volcano.
On May 6th and 7th, 2009, a diving robot named Jason 2 ROV was used to observe more closely eruptions at two eruption points of the elongated West Mata summit. The eruption sites were given the names Prometheus (at or near the summit) and Hades (a little to the southwest).
The eruption site called Hades produced a mixed eruption on the two days. At one end of the crevice, small explosions could be observed in a 5 m long crevice at a depth of 1208 m, while pillow lavas oozed out at the other end . During the following night, activity increased and the volcano hurled glowing bubbles three feet from the eruption fissure.
film records
Recordings of the diving robot were published in a video by the National Oceanic and Atmospheric Administration in December 2009.
See also
Individual evidence
- ^ Scientists Discover and Image Explosive Deep-Ocean Volcano . NOAA . December 17, 2009. Retrieved December 19, 2009.
- ↑ a b c d http://www.volcano.si.edu/volcano.cfm?vn=243130&vtab=Bulletin Smithsonian Institution, Global Volcanism Program, West Mata, Monthly Report, 06/2009